A computing system, like a server, for example, generally comprises at least one central processing unit (CPU) and a memory subsystem including a plurality of platform memory components which may be dual in-line memory modules (DIMMs), for example. Most modern servers comprise multiple processing units which share or interleave their respective memory usage among the plurality of DIMMs. In a data center, there may be a multiplicity of computing systems or servers. The memory subsystems of these computing systems consume a significant portion of the overall power of the data center. Power consumption of a data center is usually controlled by a data center manager via the operating systems of the various data center computing systems.
From time to time, a reduction in power consumption to a computing system of the center is required. The reasons for the power reduction are varied. For example, a data center may be on a power consumption budget. If a current power usage is predicted to exceed the designated power budget, the data center manager may issue commands to reduce power consumption of one or more computing systems of the center. Another possibility may be as a result of power consumption creating excessive heating in the computing system. A reduction in power consumption to one or more of the computing systems may be used as a technique to reduce the heating of the system equipment to meet a thermal budget.
If power reduction to a computing system of the center is deemed necessary, there may be only a single choice between running the server which will continue to consume the power required for total use of system memory or turning the server and its respective memory subsystem completely off to achieve the desired reduction in power consumption. More than likely, when all other means of power reduction are not sufficient, the computing system will be turned off. While this maneuver achieves the goal of power reduction, it severely and adversely affects the computing performance of the overall center. Accordingly, it is desirable to find a way to reduce power consumption of a computing system without completely eliminating it as a computing resource of the data center.